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(1 北京科技大學(xué)土木與資源工程學(xué)院， 北京 100083； 2 河北省建筑科學(xué)研究院有限公司，石家莊 050021； 3 河北省固廢建材化利用科學(xué)與技術(shù)重點(diǎn)實(shí)驗(yàn)室， 石家莊 050021)

摘要: 利用杭紹臺(tái)高速公路隧道洞砟，制備凝灰?guī)r型機(jī)制砂，分析了機(jī)制砂及石粉特性，研究其對(duì)砂漿、混凝土流動(dòng)性與強(qiáng)度的影響，利用條形篩檢測(cè)機(jī)制砂中片狀顆粒，探究不同片狀顆粒含量對(duì)砂漿與混凝土和易性的影響規(guī)律，并研究不同砂率對(duì) C30 與 C35 混凝土性能的影響。 試驗(yàn)結(jié)果表明:凝灰?guī)r型機(jī)制砂為硅質(zhì)機(jī)制砂，表面的斷鍵導(dǎo)致石粉易團(tuán)聚，對(duì)亞甲藍(lán)值不敏感，需水量大。 隨著石粉與片狀顆粒含量的增加，砂漿與混凝土的流動(dòng)性與強(qiáng)度不斷降低。 凝灰?guī)r片狀顆粒含量大于石灰?guī)r片狀顆粒含量對(duì)強(qiáng)度的影響程度，片狀顆粒含量對(duì)低水膠比砂漿流動(dòng)性及強(qiáng)度影響幅度大于高水膠比影響幅度。 考慮混凝土的工作性和抗壓強(qiáng)度，機(jī)制砂中石粉含量宜小于 8%，片狀顆粒含量宜小于 10%，選定 C30 的砂率為 43%，C35 的砂率為 41%。

關(guān)鍵詞: 凝灰?guī)r； 石灰?guī)r； 機(jī)制砂； 和易性； 流動(dòng)性； 石粉； 片狀顆粒

中圖分類號(hào):TU525 文獻(xiàn)標(biāo)志碼:A 文章編號(hào):1002￣848X(2022)02￣0120￣07

DOI:10. 19701 / j.jzjg.LS201854

Study on workability and mechanical properties of tuff￣typed tunnel ballast machine￣made sand concrete

ZHANG Guangtian1，2，3， LIU Juanhong1， LIU Kun1， FU Shifeng2，3， LIU Dongji2，3

(1 College of Civil and Resources， University of Science and Technology Beijing， Beijing 100083， China； 2 Hebei

Academy of Building Research， Shijiazhuang 050021， China； 3 Hebei Province Science and Technology Key Laboratoryof Solid Waste for Building Materials， Shijiazhuang 050021， China)

Abstract: Using the tunnel ballast of Hangzhou shaotai expressway， tuff￣typed machine￣made sand was prepared. Thecharacteristics of machine￣made sand and stone powder were analyzed， and their effects on the fluidity and strength ofmortar and concrete were studied. Strip sieve was used to detect the flake particles in the machine￣made sand and explorethe influence of different flake particles contect on the workability of mortar and concrete， and the impact of different sandrates on concrete performance of C30 and C35 was studied. The test results show that the tuff￣typed machine￣made sand issiliceous machine￣made sand， and the broken bond on the surface causes the stone powder to easily agglomerate， and it isnot sensitive to the methylene blue value， and requires a large amount of water. As the content of stone powder and flakyparticles increases， the fluidity and strength of mortar and concrete continue to decrease. The influence of contect of flakeparticles of tuff on the strength is greater than that of contect of limestone flake particles， and the influence of contect offlake particles on the fluidity and strength of mortar with low water￣binder ratio is greater than that of high water￣binderratio. Considering the workability and compressive strength of concrete， the stone powder content in machine￣made sandshould be less than 8%， and the contect of flake particles should be less than 10%， and the selected C30 sand rate is43%， and the C35 sand rate is 41%.

Keywords: tuff； limestone； machine￣made sand； workability； flowability； stone powder； flake particle

∗國(guó)家自然科學(xué)基金面上項(xiàng)目(51678049)，國(guó)家自然科學(xué)基金重點(diǎn)項(xiàng)目(51834001)，河北省重點(diǎn)研發(fā)計(jì)劃(19274104D)。

第一作者:張廣田，博士，高級(jí)工程師，主要從事固廢資源化利用、高品質(zhì)砂石、尾礦資源化利用等方面研究，Email:syzx1206@163.com。

[引用本文] 張廣田，劉娟紅，劉昆，等. 凝灰?guī)r型隧道洞砟機(jī)制砂混凝土和易性與力學(xué)性能研究[ J]. 建筑結(jié)構(gòu)，2022，52(2):120￣126. ZHANG Guangtian， LIU Juanhong， LIU Kun， et al. Study on workability and mechanical propertiesof tuff￣typed tunnel ballast machine￣made sand concrete[J]. Building Structure，2022，52(2):120￣126.